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1.
Summary Twenty-four patients with a variety of solid tumors entered a Phase I trial with 4-demethoxydaunorubicin, a new analogue of daunorubicin. The drug was given as a single oral dose of 10–60 mg/m2 repeated every 3–4 weeks.Leukopenia was the dose-limiting toxicity. Other toxic effects included mild to moderate nausea and vomiting. Sixty mg/m2 was found to be the maximum tolerated dose in patients with fair tolerance to chemotherapy and normal liver function. Similar hematologic toxicity was reported in patients with very extensive prior chemotherapy or diffuse bone and/or liver metastases receiving 50 mg/m2. However, the wide range of the WBC nadirs reported with the same dose in good risk cases, suggest that 40 mg/m2, increased up to 50 mg/m2 in the absence of significant myelotoxicity, could be more safely proposed as starting dose for Phase II trials. Pharmacokinetic studies were performed in five patients given a single dose of 40–60 mg/m2. IMI-30 (NSC 256439) appears to be rapidly absorbed and rapidly eliminated from plasma by means of a rapid and extensive biotransformation to 13-OH-idarubicin. The 13-dihydroderivative was present at higher and more prolonged levels than the parent compound, with an elimination half-life of about 40 hours.Presented in part at the Third NCI-EORTC Symposium on New Drugs in Cancer Therapy, Brussels, October 13–17, 1981.  相似文献   

2.
Summary Mitoxantrone (Novantrone®) and prednimustine (Sterecyt®) are both active as single agents in the treatment of unfavorable non-Hodgkin lymphoma (UNHL). The efficacy and toxicity of the combination of these agents (NOSTE) was evaluated in 28 patients with advanced histopathologically proven UNHL who were not eligible for aggressive conventional chemotherapy. The median age was 68, range 45–84. Sixteen patients were previously untreated. Eleven patients had received doxorubicin or epidoxorubicin containing regimens and 1 patient had received CVP as first line therapy. MUGA scan was used in monitoring cardiac function in patients with cardiac risk. Novantrone® was administered at a dose of 8 mg/m2 IV on days 1 and 2 and Sterecyt® as an absolute dose 100 mg/ 1.6 m2–150 mg/> 1.6 m2 on days 1 through 5. The regimen was repeated every 4th week. The number of courses per patient ranged from 2 to 10. Objective response was obtained in 22 (78%) patients (20 CR and 2 PR). No response occurred in 6 patients (4 SD, 2 PD). Decreased left ventricular ejection fraction was recorded in 1 patient who suffered from asthma and ischemic heart disease. Hematological toxicity was tolerable. Gastrointestinal toxicity was rare. No hair loss was observed. After a median follow-up of 28 months the crude survival was 46%. Twelve of twenty complete responders are still in remission, the median duration of remission is 28.3 months, range 15–37.NOSTE in this pilot study showed a high response rate, good tolerance and mild toxicity. NOSTE reduced the discomfort associated with conventional dose anthracycline-containing regimens and could be safely used in the treatment of elderly patients.  相似文献   

3.
Summary Twenty-three evaluable patients with advanced gastric adenocarcinoma were treated with trimetrexate at doses of 8–12 mg/m2 intravenously daily for five days, with cycles repeated every 21 days. One complete response was seen for an overall response rate of 4% (95% confidence interval 0–22%). Hematologie toxicities of grade 3 were seen in 10/23 patients, and overall any grade 3 or greater toxicity was seen in 14/ 23 patients. Trimetrexate has minimal activity against gastric adenocarcinoma in this study, and no further investigation of this agent at this dose and schedule is recommended in this disease.  相似文献   

4.
Interferon (IFN) and conventional cytotoxic chemotherapeutic agents have been successfully combined in various studies. Alpha difluoromethylornithine (DFMO) is a novel antitumor agent which is an inhibitor of polyamine metabolism. A phase I study of IFN 24 × 106 U/m2/day IM (days 3–7), DFMO 9 gm/m2 p.o. daily (days 1–7), and a variable dose of doxorubicin starting at 20 mg/m2 (day 6), of each 28 day cycle was performed. The aim of the study was to determine the maximally tolerable dose of doxorubicin in this combination. Three patients were treated with doxorubicin at 20 mg/m2 and six patients at 40 mg/m2. The dose limiting toxicities were neutropenia, fatigue and fever. All other toxicities were mild and there was no grade IV toxicity. A doxorubicin dose of 40 mg/m2 produced tolerable toxicity and is recommended for phase II studies. No major antitumor effects were seen.  相似文献   

5.
Summary Based upon the hypothesis that dipyridamole would potentiate the cytotoxicity of mitoxantrone and the combination of 5-fluorouracil (5-FU) and leukovorin, we performed a phase I/II trial of the combination of dipyridamole, 5-FU, leukovorin, and mitoxantrone in patients with metastatic breast cancer. The dose of dipyridamole was fixed at 175 mg/m2 by mouth every 6 h (700 mg/m2/day), based upon a previous phase I trial of oral dipyridamole with 5-FU and leukovorin. Dipyridamole therapy began 24 h prior to the first dose of chemotherapy and continued until 24 h after the last dose of chemotherapy for each course of treatment. At the initial dose level, leukovorin 200 mg/m2 was given intravenously immediately prior to 5-FU 375 mg/ m2 intravenously on days 1–5. Mitoxantrone 6 mg/m2 was given as a single dose on day 3. Unacceptable toxicity was observed at this dose level, leading to successive dose decrements rather than dose increments. The maximum tolerated dose was leukovorin 200 mg/m2 days 1–2, 5-FU 375 mg/m2 days 1–2, mitoxantrone 6 mg/m2 on day 2, and dipyridamole 175 mg/m2 every 6 h on days 0–3. Two responses were produced in 15 patients. This regimen is not recommended for further investigation in the treatment of breast cancer.  相似文献   

6.
Summary Gemcitabine (GEM) is a novel deoxycytidine analogue which has shown promising antitumor activity in solid tumor models and a broad range of schedule-dependent MTDs (12-4560 mg/m2) in preliminary clinical studies. The present phase I trial evaluated escalating doses of weekly GEM using a 30-min infusion at a starting dose-level of 300 mg/m2/wk x 3 every 28 days.At least 3 patients entered each dose-level step and 3 more cases were treated when significant toxicity was seen. A total of 39 patients with various advanced solid tumors and prior chemotherapy entered this study.Six escalation steps (102 courses) were tested to define the MTD at 1,370 mg/m2/wk. No definite dose-effect relationships were observed for myelosuppression up to 1,095 mg/m2/wk. However, increased severity of leucopenia (dose-limiting) and greater non-hematologic toxicity as well as a higher number of toxic treatment delays, requiring subsequent dose attenuation in 6 out of 12 patients, were observed at 1,370 mg/ m2/wk. In all, 6 out of 11 patients experiencing WHO grade 3 toxicity (11/21 events recorded in 11/18 courses) were treated at the MTD. Clinically significant toxicity included (patients with WHO grade 2–3): leucopenia (44%), thrombocytopenia (26%), anemia (23%), fever (69%), emesis (38%) and AST/ALT rise (26%). Mild proteinuria, ankle edema, skin rash, hair loss and mucositis were seen in 5%.The good tolerability and the evidence of antitumor activity of GEM at doses 875 mg/m2/wk (1 CR and 3 PRs in 15 bladder cancer patients) encourage further phase II studies at much higher dose-levels (1,370 mg/m2) than previously suggested.  相似文献   

7.
Background: Gemcitabine and mitoxantrone are active agents for the treatment of metastatic breast cancer. Due to different modes of action and a favorable toxicity profile they are suitable for combination therapy. This phase I trial was initiated to determine the optimal doses for the combination in patients with metastatic breast cancer. Secondary objectives included the evaluation of the safety and efficacy of the regimen. Patients and methods: Patients with metastatic breast cancer were treated with gemcitabine (1000–1400 mg/m2) on days 1, 8 and 15 and mitoxantrone (10–14 mg/m2) on day 8. Treatment was repeated every 4 weeks for a maximum of 8 cycles. Doses were assigned at registration according to the escalation scheme. Results: Twenty-six patients received a total of 93 cycles at 5 different dose levels. The maximum tolerated doses were 1200 mg/m2 gemcitabine and 14 mg/m2 mitoxantrone with grade 4 neutropenia being the dose limiting toxicity. Recommended phase II doses, however, are gemcitabine 1200 mg/m2 and mitoxantrone 12 mg/m2 based on a similar median dose intensity and a more favorable toxicity profile. Predominant toxicity was myelosuppression. Most common non-hematological toxicities were nausea, vomiting, alopecia and elevation of liver enzymes. Twenty-one patients were assessable for response. Four patients achieved a partial response accounting for an overall response rate of 19%. In addition, 12 patients (57%) had stable disease and 5 patients (24%) failed to response to the treatment. Median duration of response and duration of clinical benefit were 14 and 9 months, respectively. Conclusion: In this phase I study of gemcitabine and mitoxantrone, the DLT was neutropenia. Recommended phase II doses are gemcitabine 1200 mg/m2 and mitoxantrone 12 mg/m2.  相似文献   

8.
Summary Based on the activity of menadione (M) in the human tumor stem cell assay, we conducted a phase I trial of M in patients with advanced cancer. Forty patients (19 men, 21 women) were treated with 90 courses of M; 82 treatment courses are evaluable for toxicity. The median patient age, Karnofsky performance status, and number of prior chemotherapy regimens were 61 years (range 32–74 years), 80% (range 50–100%), and two, respectively. M was given by a short (1–5 h) intravenous infusion every 3 weeks, starting at 40 mg/m2 and escalating by modified Fibonacci scheme to 1360 mg/m2. Toxicity was graded according to the Southwest Oncology Group toxicity scale with defined hypersensitivity reaction (HSR) scales. No grade 2 hematologic toxicity was observed. Non-hematologic toxicity consisted of a HSR syndrome of paresthesiae of the extremities, facial flushing, burning of the eyes and mucous membranes, chest pain and dyspnea. HSR was defined as Grade I toxicity by the presence of facial numbness, flushing, and/or a tingling sensation or burning of the eyes and mucous membranes. Grade II toxicity was defined as the presence of the same above symptoms plus chest tightness, paresthesiae of extremities and/or dyspnea and chest pain. These toxicities were grade 1 in 3 of 4 patients at a dose of 840 mg/m2. At 1360 mg/m2, 2 of 13 patients suffered grade 1 HSR and 7 of 13 grade 2 HSR No objective partial or complete responses were observed. Plasma menadione concentrations peaked at 1.9–7.4 M during the infusion in 3 patients receiving 1360 mg/m2. Further phase 1 and 2 combination trials using longer infusion durations have resulted from this trial.  相似文献   

9.
Precis: UFT 300 mg/m2/day and leucovorin 90 mg/day could be administered safely to patients with advanced biliary cancer with good performance status; however, this combination and schedule of 28-day administration has no activity in this disease.Purpose: To determine the activity and evaluate the toxicity of uracil and tegafur in a 4:1 molar concentration ratio (UFT; Bristol-Myers Squibb, Wallingford, CT) plus oral calcium leucovorin in the treatment of patients with advanced biliary (gallbladder and bile duct) carcinoma.Patients and methods: Thirteen patients with advanced measurable biliary carcinoma were enrolled onto the trial. All patients had a Karnofsky performance status 60%, platelet count 75,000/L, total bilirubin 2.0× institutional upper limit of normal but otherwise normal liver and kidney function profile and bidimensionally measurable disease by CT scan or ultrasound examination. None of these patients previously received cytotoxic chemotherapy or radiation therapy for advanced disease. Patients received 300 mg/m2/d UFT plus 90 mg/d leucovorin administered orally in divided daily doses every 8 hours for 28 days repeated every 35 days. Objective tumor response, the primary endpoint of this trial, was evaluated after two courses of therapy. Other endpoints included toxicity, time to progression, and overall survival.Results: All patients were evaluable for response and toxicity. No complete or partial responses were observed in this trial. Four patients had stable disease lasting 17, 30, 33, and 35 weeks, respectively. The median (range) time to progression and survival were 9 (1–35) and 28 (1–61) weeks, respectively. Treatment-related toxicity was mild with severe (grade 3 or 4) diarrhea seen in 2 (15%). Grade 3–4 hyperbilirubinemia (31%) and nausea/vomiting (31%) were observed and likely related to the underlying disease. Grade 1 and 2 toxic effects included mainly anorexia and fatigue.Conclusion: UFT 300 mg/m2/d plus oral leucovorin 90 mg/d administered for 28 days repeated every 35 days is ineffective in the treatment of advanced biliary carcinoma.  相似文献   

10.
Purpose: Inherited variations in drug metabolizing enzymes may influence drug efficacy. This phase II study assesses the impact of second-line weekly irinotecan (CPT-11)/docetaxel in non-small cell lung cancer (NSCLC) patients, and gauges the uridine diphosphate glucuronosyl transferase (UGT1A1) polymorphism influence in toxicity and antitumor activity. Experimental Design: Fifty-one patients with NSCLC treated with at least one prior chemotherapy regimen were enrolled. Patients received irinotecan 70mg/m2 followed by docetaxel 25mg/m2. Both drugs were given on days 1, 8, and 15 every 28 days. UGT1A1 polymorphism were analyzed in blood samples of 47 patients. The UGT1A1 polymorphism are classified according to the number of TA repeats in the promoter region of this gene. Results: Three patients (6%) achieved a partial response and nineteen patients (37%) had stable disease. Median survival was 8 months (95% CI: 4.8–11.2) and 1-year survival 30%. Grade 3–4 hematologic toxicity was low (less than 10% of patients); 15% of patients had grade 3 asthenia and 25% of patients had grade 3/4 diarrhea. The frequency of UGT1A1 genotypes was as follows: 6/6 49%, 6/7 36%, and 7/7 15%. No differences in toxicity were observed according to UGT1A1 polymorphism. A nonsignificant improvement in time to progression (4 vs. 3 months) and median survival (11 vs. 8 months) was detected in patients with the variant alleles (6/7 and 7/7). Conclusions: This weekly irinotecan/docetaxel regimen has shown an acceptable toxicity profile while encouraging median and 1-year survival in heavily pretreated NSCLC patients. The tendency to better prognosis in patients carrying the variant genotypes 6/7 and 7/7 of UGT1A1 gene requires further validation.  相似文献   

11.
Gemcitabine is a novel nucleoside analog which demonstrated a broad spectrum of preclinical acitivity in solid tumor models, and responses in patients with pancreas cancer during phase I evaluation. Patients with measurable adenocarcinoma of the pancreas who had received no previous chemotherapy were eligible for this multicenter phase II clinical trial. Gemcitabine 800 mg/m2 was administered intravenously weekly for 3 consecutive weeks, followed by one week rest, every 4 weeks. Forty-four patients entered the trial; 35 had at least 2 cycles of therapy. Partial response was observed in 5 patients (11%, estimated 95% confidence interval 2–20%), with a median duration of 13 months. All responding patients had stabilization or improvement in performance status. Fourteen patients had stable disease of 4 or more months. The median WBC nadir was 3.8 × 103/l (range 1.6–9.3) and the median absolute neutrophil (ANC) nadir was 2.0 × 103/l (range 0.4–7.2). Thrombocytopenia - 100.0 × 103/l was observed in 15 patients; the median platelet nadir was 123.0 (range 30.0–245.0). All patients experienced a mild to moderate flu-like syndrome. In addition, one patient had a mild hemolytic-uremic syndrome which appeared related to gemcitabine therapy. Gemcitabine demonstrated marginal activity in this resistant neoplasm, without excessive toxicity. Further evaluation, including the use of more intense dosing and/or combination therapy, is warranted.  相似文献   

12.
Summary Fourteen patients with pediatric malignant solid tumors, median age 15 years, received 22 courses of bisantrene in a Phase I study. Dosage escalations ranged from 10 to 120 mg/m2 daily for 5 consecutive days. Toxicity included myelosuppression and phlebitis. A sensitive (detection limit of 2 ng/ml) and specific HPLC method was developed to quantitate bisantrene in patient's plasma and urine. Peak plasma concentrations at the end of 60 minute infusions ranged from 568 ng/ml at 10 mg/m2 to 6800 ng/ml at the 100 mg/m2 dosage. The elimination half life (T 1/2) averaged about 10 hours but increased to 20 hours in a patient with liver disease. Only 2.4–10% of the bisantrene dose was eliminated in the urine suggesting that the liver may be the major route of elimination for this antineoplastic anthracene derivative.  相似文献   

13.
Summary Twenty-six patients with various solid tumors entered a Phase I trial with 4 -Deoxydoxorubicin (Esorubicin, IMI-58), a new doxorubicin analogue. The drug was administered weekly i.v. for 3–4 weeks. Leukopenia proved to be dose limiting. The maximum tolerated dose (MTD) was reached at 20 mg/m2 weekly for 3 weeks. For Phase II trials, a weekly dose of 15 and 17.5 mg/m2 can be proposed for poor and good risk patients respectively. Non-hematologic toxicity was minimal. Phase II trials with this new anthracycline are warranted.  相似文献   

14.
Summary CC-1065 is a unique alkylating agent that preferentially binds in the minor groove of double-stranded DNA at adenine-thymine-rich sites. Although it has broad antitumor activity in preclinical models its development was discontinued because of deaths observed during preclinical toxicology studies. Adozelesin is a potent synthetic analog that was chosen for clinical development because it had a similar preclinical antitumor spectrum, but did not produce deaths similar to CC-1065 at therapeutic doses. Phase I evaluations using a variety of Adozelesin treatment schedules have been conducted. This report describes our experience using a multiple dose treatment schedule. Endpoints including antitumor response, maximum tolerated dose, dose limiting toxicity as well as other toxicities and the recommended Phase II starting dose were determined. Adozelesin was given as a 10 minute IV infusion for 5 consecutive days every 21 days or upon recovery from toxicity. The dose range evaluated was 6–30 mcg/m2/day. All patients had refractory solid tumors and had received prior cytotoxic treatment. Thirty-three patients (22 men: 11 women) were entered onto the study and 87 courses were initiated. Dose limiting toxicity was cumulative myelosuppression (leucopenia, thrombocytopenia). The maximum tolerated dose was 30 mcg/m2/day. The only other significant toxicity was an anaphylactoid syndrome that occurred in 2 patients. A partial response was observed in a patient with refractory soft tissue sarcoma. The recommended Phase II starting dose of Adozelesin using a 10 minute IV infusion for 5 consecutive days is 25 mcg/m2/day to be repeated every 4–6 weeks to allow recovery from myelotoxicity, based on our experience. Additional Phase I and II studies with Adozelesin are recommended.  相似文献   

15.
The topoisomerase I inhibitor topotecan has shown activity in acute myeloid leukemia (AML) and myelodysplastic syndromes. The present study was designed to assess whether topotecan with cytosine arabinoside (ara-C) or with etoposide (VP-16) should be studied in phase II trials in patients with refractory or relapsed AML.Patients with refractory or relapsed AML were assigned to one of 3 strata defined by expected CR rates of 7%, 20% and 40%, then randomly assigned to receive topotecan (d1-5) and ara-C (1 g/m2 over 2 hours; d1-5), topotecan (d1-5) followed by VP-16 (250 mg/m2 twice daily, d6-7), or VP-16 (250 mg/m2 twice daily d1-2) followed by topotecan (d3–d7). A dose-finding phase was conducted in the poorest stratum of each arm (topotecan starting dose: 1.0 mg/m2/day × 5). A Bayesian pre-phase II selection design was used to assess whether the CR rate with a given arm was sufficient to merit investigation in phase II.Thirty-seven patients, median age 58 years, were treated. Their median first CR duration was 28 weeks and 24% were primary refractory. Grade 3–4 mucositis occurred in the initial patients in the topotecan VP-16, but not in the topotecan + ara-C or VP-16 topotecan arms. Consequently, in subsequent patients, the topotecan dose was lower in the topotecan VP-16 than in the other 2 arms (1.0 vs 1.25 mg/m2 daily × 5) and the VP-16 dose was lower in the topotecan VP-16 arm (200 vs 250 mg/m2 twice daily × 2). One CR occurred (topotecan VP-16 arm), and the treatment arms were terminated after 10, 15, and 12 patients were treated on the topotecan + ara-C, topotecan VP-16, and VP-16 topotecan arms, respectively. The principal cause of failure was insufficient anti-leukemia effect rather than death on study, and toxicity was minimal at the final doses used.We concluded that none of the combinations studied here warrants phase II evaluation in very poor prognosis AML salvage patients.  相似文献   

16.
Summary Purpose: VNP40101M is a new alkylating agent that demonstrated broad anti-tumor activity in murine tumor models. A phase I trial was initiated to determine the toxicities, maximum tolerated dose, and pharmacokinetics of VNP40101M by short IV infusion. Study design: The starting dose was 3 mg/m2 every four weeks, and was escalated in successive cohorts as follows: 6, 12, 24, 40, 60, 80, and 100 mg/m2. Beyond 100 mg/m2, dose increments were 25%. Initially, 1–2 patients were assigned to a dose level. Intra-patient dose escalation was permitted. With the first instance of a drug-related grade 2 adverse event, all dose levels required assessment of 3–6 patients. Pharmacokinetic parameters were assessed in the first cycle and any cycle with a change in dose. Results: Twenty-six patients in 13 dose levels ranging from 3–305 mg/m2 were evaluated. Dose-related thrombocytopenia was the major toxicity, with the nadir occurring at a median of day 27. At 305 mg/m2, six of eight patients developed grade 3 thrombocytopenia, including one event that met the definition for DLT. Other dose-related toxicities included moderate granulocytopenia, anemia, and a mild infusion-related syndrome consisting of acute headache and facial flushing. The granulocyte nadir occurred at a median of day 34, and recovery of both thrombocytopenia and neutropenia to < grade 2 occurred at a median of day 43. VNP40101M peak plasma concentrations and AUC were linear with dose. The elimination half-life was short and estimated to be approximately 15 minutes. Conclusions: The MTD and recommended dose for phase II trials is 305 mg/m2 every six weeks. Phase II trials in less heavily pre-treated patient populations are warranted.Supported by Vion Pharmaceuticals, Inc.  相似文献   

17.
Summary We evaluated the antitumoral efficacy and safety of CPT-11 125 mg/m2 (weekly 90 min i.v. infusion; days 1, 8 and 15) combined with UFT (oral combination of tegafur and uracil) 200 mg/m2/day plus leucovorin (LV) 45 mg/m2/day (both divided into three separate oral doses every 8 h, days 1–21) every 4 weeks as first-line chemotherapy of metastatic colorectal cancer (CRC). Fifty-three patients 18 years old with histologically confirmed diagnosis of advanced CRC and bidimensionally measurable disease were enrolled. Three patients (6%) showed CR and 8 patients (15%) showed PR (ORR = 21% (95% CI, 10–32). Stable disease was reported in 19 patients (36%) [tumor control rate = 57% (95% CI, 43–70)]. The median time to progression and overall survival were 7.9 and 18.2 months, respectively (1-year rate = 74%; 2-years rate = 26%). CPT-11/UFT/LV treatment was well tolerated: the most reported grade 3/4 toxicities were neutropenia (11% of patients) and delayed diarrhea (28% of patients). No significant differences in response rate, survival or toxicity were found between younger (65 years) and older patients (> 65 years). Weekly CPT-11 plus UFT/LV was found effective and safe as first-line chemotherapy for metastatic CRC. The addition of CPT-11 to UFT/LV doubled the response rate compared to the results previously reported with UFT/LV, while myelosuppression remained low.  相似文献   

18.
Patients with a pathologically proven diagnosis of malignant melanoma were entered into a phase II trial of bisantrene. Eligibility criteria included: measurable, metastatic disease; performance status 0–2 SWOG; and adriamycin total cumulative dose of < 400 mg/m2. The initial bisantrene dosing schedule was 260 mg/m2 every three weeks for good risk patients. Due to the absence of an objective response and the lack of severe toxicity in the first 25 bisantrene treated patients, the starting dose was increased to 300 mg/m2 for good risk patients. Fifty-one patients received a median of two bisantrene courses (range 1–11 courses). Leukopenia was the major toxicity. Fifteen (68%) of the 22 good risk, intermediate dose patients (260 mg/m2), and 8 (80%) of the 10 good risk, high dose patients (300 mg/m2) evaluable for toxicity experienced mild-severe leukopenia. None of the 51 patients experienced a complete or partial response to bisantrene. Median survival was 3.3 months. We conclude that bisantrene is ineffective in the treatment of metastatic melanoma. Address for offprints: Southwest Oncology Group (SWOG-8118), Operations Office, 5430 Fredericksburg Road, Suite #618, San Antonio, TX 78229, USA  相似文献   

19.
Thirteen patients with metastatic renal cancer were treated in a phase II trial with interleukin-2, 21.6 million IU/m2 intravenously daily for five days on two consecutive weeks, starting 3 days after the administration of low dose cyclophosphamide 350 mg/m2 intravenously. Treatment cycles were repeated every 21 days. No responses were seen (95% Confidence Interval: 0–22%). The most common toxicities were fever, fatigue, hypotension, nausea/emesis, and myalgia/arthralgia. There were 11 episodes of Grade III toxicity including Grade III hypotension in 7 patients. Because of the significant toxicity and the lack of observed response, the study was discontinued. Cyclophosphamide and interleukin-2 at the dose and schedule used in this study has considerable toxicity and is unlikely to improve on response rates previously seen with other IL-2-based regimens in metastatic renal cancer.  相似文献   

20.
1-Methyl-4-phenylpyridinium (MPP+), the neurotoxic metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), is efficiently taken up and accumulated by rat hepatocytes. However, the nature of the mechanism(s) involved in the hepatic uptake of MPP+ remains partially unknown. The aim of the present study was to further characterize the hepatic uptake of 3H-MPP+, namely by investigating the interactions of catecholamines (which are also efficiently taken up by rat hepatocytes) with MPP1 transport.The accumulation of 3H-MPP+ in isolated rat hepatocytes occurred through saturable and non-saturable mechanisms. The kinetics of the saturable component of 3H-MPP+ uptake was as follows: Vmax = 181.3 ± 11.1 pmol mg protein–1 min–1 and Km = 47.1 M (27.9, 66.3) (n = 5). The diffusion constant (in ml mg protein–1 min–1) for the non-saturable uptake of 3H-MPP+ was 0.00068 (0.00052, 0.00083) (n = 5). From the analysis of the time course of 3H-MPP+ accumulation at a substrate concentration of 100 nM 3H-MPP+, it was found that the rate constant of inward transport of 3H-MPP+ into hepatocytes (kin) was 15.7 ± 3.8 l mg protein–1 min–1, the rate constant of outward transport of 3H-MPP+ from hepatocytes (kout) was 0.077 ± 0.023 min–1 and the equilibrium accumulation (Amax) of 3H-MPP+ was 20.2 ± 2.0 pmol mg protein–1 (n = 36). Decynium22 (1,1-diethyl-2,2-cyanide; 1 M) significantly reduced kin to 6.1 ± 1.8 l mg protein–1 min–1 (P < 0.05) and the equilibrium accumulation (Amax) of 3H-MPP+ to 9.6 ± 1.3 pmol mg protein–1 (P < 0.005) (n = 36). 3H-MPP+ accumulation (in cells incubated with 200 nM 3H-MPP+) was sensitive to (–)-adrenaline, (–)-isoprenaline, (–)-dopamine, (±)-adrenaline and (–)-noradrenaline. The most potent catecholamine in inhibiting 3H-MPP+ uptake was (–)-adrenaline, with an IC50 of 99 (22, 449) M (n = 6). (–)-Adrenaline competitively inhibited 3H-MPP+ uptake, as it significantly increased the Km value of 3H-MPP+ uptake (to 125.4 M (63.6; 187.1); P < 0.02; n = 3) but did not change the Vmax value. The cyanide-derivatives decynium22 and cyanine863 (1-ethyl-2-([1,4-dimethyl-2-phenyl-6-pyrimidinylidene]methyl)quinolinium), which inhibit uptake2 as well as the apical type of the renal transporter for organic cations, potently inhibited 3H-MPP+ uptake with IC50's of 1.4 (0.4–5.3) (n = 6) and 6.5 (2.6–16) (n = 4) M, respectively. Under conditions of monoamine oxidase (MAO) and catechol-O-methyl transferase (COMT) inhibition with either pargyline (500 M + Ro01-2812) (3,5-dinitropyrocatechol; 2 M) or pargyline (500 M) + U-0521(3,4-dihidroxy-2-methyl-propiophenone; l2 M)), (–)-adrenaline (up to 1 mM) had no inhibitory effect on the uptake of 3H-MPP+. Moreover, the uptake of 3H-MPP+ in the presence of pargyline + Ro 01-2812 was significantly lower (66.9 ± 30.4%; P < 0.05; n = 4) than in the absence of these compounds. Therefore, the effect of these MAO and COMT inhibitors on 3H-MPP+ uptake was examined. Interestingly enough, pargyline, Ro 01-2812 and U-0521 were found to inhibit the uptake of 3H-MPP+ (in cells incubated with 200 nM 3H-MPP+): 500 M pargyline, 2 M Ro 012812 and 100 M U-0521 decreased the accumulation of 3H-MPP+ to 38.1 ± 6.8 (n = 5), 60.5 ± 10.1(n = 7) and 71.3 ± 14.5 (n = 7) % of control, respectively.It is concluded that 3H-MPP+ is efficiently taken up by rat hepatocytes by a carrier-mediated mechanism sensitive to catecholamines, decynium22 and cy anine863, and to the enzyme inhibitors pargyline, Ro 01-2812 and U-0521.  相似文献   

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